Note 8 - Deposits - Summary of Deposits (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Non-interest bearing	$ 13,664,986	$ 14,057,719
Non-interest bearing checking, percent	5.78%	6.29%
Interest bearing checking	$ 62,473,596	$ 54,292,074
Interest bearing checking, percent	26.44%	24.30%
Money market	$ 22,452,316	$ 25,032,543
Money market, percent	9.50%	11.20%
Savings	$ 25,008,034	$ 25,719,932
Savings, percent	10.58%	11.51%
Certificates of deposit	$ 112,714,572	$ 104,346,261
Certificates of deposit, percent	47.70%	46.70%
Interest bearing	$ 222,648,518	$ 209,390,810
Interest bearing, percent	94.22%	93.71%
Total	$ 236,313,504	$ 223,448,529
Total, percent	100.00%	100.00%